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排序方式: 共有9317条查询结果,搜索用时 312 毫秒
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Susanna Zanutto Chiara Maura Ciniselli Antonino Belfiore Mara Lecchi Enzo Masci Gabriele Delconte Massimo Primignani Giulia Tosetti Marco Dal Fante Linda Fazzini Aldo Airoldi Marcello Vangeli Francesca Turpini Giovanni Giuseppe Rubis Passoni Paolo Viaggi Monica Arena Roberta Ilaria Olimpia Motta Anna Maria Cantù Cristiano Crosta Giuseppe De Roberto Francesca Iannuzzi Andrea Cassinotti Valentina Dall'Olio Laura Tizzoni Gabriella Sozzi Emanuele Meroni Luigi Bisanti Marco Alessandro Pierotti Paolo Verderio Manuela Gariboldi 《International journal of cancer. Journal international du cancer》2020,146(4):1164-1173
Colorectal cancer (CRC) screening programs help diagnose cancer precursors and early cancers and help reduce CRC mortality. However, currently recommended tests, the fecal immunochemical test (FIT) and colonoscopy, have low uptake. There is therefore a pressing need for screening strategies that are minimally invasive and consequently more acceptable to patients, most likely blood based, to increase early CRC identification. MicroRNAs (miRNAs) released from cancer cells are detectable in plasma in a remarkably stable form, making them ideal cancer biomarkers. Using plasma samples from FIT-positive (FIT+) subjects in an Italian CRC screening program, we aimed to identify plasma circulating miRNAs that detect early CRC. miRNAs were initially investigated by quantitative real-time PCR in plasma from 60 FIT+ subjects undergoing colonoscopy at Fondazione IRCCS Istituto Nazionale dei Tumori, then tested on an internal validation cohort (IVC, 201 cases) and finally in a large multicenter prospective series (external validation cohort [EVC], 1121 cases). For each endoscopic lesion (low-grade adenoma [LgA], high-grade adenoma [HgA], cancer lesion [CL]), specific signatures were identified in the IVC and confirmed on the EVC. A two-miRNA-based signature for CL and six-miRNA signatures for LgA and HgA were selected. In a multivariate analysis including sex and age at blood collection, the areas under the receiver operating characteristic curve (95% confidence interval) of the signatures were 0.644 (0.607–0.682), 0.670 (0.626–0.714) and 0.682 (0.580–0.785) for LgA, HgA and CL, respectively. A miRNA-based test could be introduced into the FIT+ workflow of CRC screening programs so as to schedule colonoscopies only for subjects likely to benefit most. 相似文献
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Maria Ricci Agostino Chiaravalloti Alessandro Martorana Giacomo Koch Vincenzo De lucia Gaetano Barbagallo Orazio Schillaci 《Annals of nuclear medicine》2020,34(4):254-262
The aim of our study was to investigate the impact of the epsilon phenotype in brain glucose consumption in a population with Alzheimer’s disease. Statistical Parametric Mapping (SPM8) was used to investigate differences in brain glucose consumption (as detectable by means of 18F FDG-PET/CT) in the population examined. A total of 129 patients (72 females and 57 males) with a diagnosis of probable AD according to the NINCDS-ADRDA criteria underwent the PET/CT examination. The mean (SD) age of the patients was 70 (± 7) years; the mean Mini-Mental State Examination was 19(± 5.6). 59 expressed epsilon 4 phenotype (E4) and 70 expressed the epsilon 3 phenotype (E3). Cerebral spinal fluid amyloid, tau, and t-tau have been measured resulting equal to 367.4 (± 149.1), 584.7 (± 312.1), and 79.2(± 45.9) pg/ml, respectively. Patients with confirmed amyloid and Tau changes were classified as AD. Patients with amyloid changes but negative Tau, considered as high risk of AD, were classified as IAD. Age, sex, MMSE, scholarship, and CSF parameters were used as a covariate in the SPM analyses. We did not find significant differences in age, gender, and MMSE and CSF parameters among groups. In the analysis of the AD group as compared to AD-E3, AD-E4 subjects show a significant reduction of brain glucose consumption in inferior frontal gyrus bilaterally (BA 45, BA 47). In the analysis of the IAD group as compared to IAD-E3, IAD-E4 subjects show a significant reduction of brain glucose consumption in right in medial, middle, and superior frontal gyrus (BA10, BA11), and in left medial and middle frontal gyrus (BA10, BA11). The differences between IAD-E3 and AD-E3 and between IAD-E4 and AD-E4 (and vice versa analysis) resulted not significant. APO-e4 is related to a major involvement of the frontal cortex confirming its role of risk factor in AD, while APO-3 seems not related to a specific pattern, supporting the hypothesis of neutral/protective role in AD. 相似文献
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Rosa Della Monica Mariella Cuomo Roberta Visconti Annabella di Mauro Michela Buonaiuto Davide Costabile Giulia De Riso Teodolinda Di Risi Elia Guadagno Roberto Tafuto Sabrina Lamia Alessandro Ottaiano Paolo Cappabianca Maria Laura Del Basso de Caro Fabiana Tatangelo Juergen Hench Stephan Frank Salvatore Tafuto Lorenzo Chiariotti 《Oncology research》2020,28(9):837-845
Unresectable neuroendocrine neoplasms (NENs) often poorly respond to standard therapeutic approaches.
Alkylating agents, in particular temozolomide, commonly used to treat high-grade brain tumors including glioblastomas, have recently been tested in advanced or metastatic NENs, where they showed promising response
rates. In glioblastomas, prediction of response to temozolomide is based on the assessment of the methylation
status of the MGMT gene, as its product, O6
-methylguanine-DNA methyltransferase, may counteract the damaging effects of the alkylating agent. However, in NENs, such a biomarker has not been validated yet. Thus, we
have investigated MGMT methylation in 42 NENs of different grades and from various sites of origin by two
different approaches: in contrast to methylation-specific PCR (MSP), which is commonly used in glioblastoma
management, amplicon bisulfite sequencing (ABS) is based on high-resolution, next-generation sequencing
and interrogates several additional CpG sites compared to those covered by MSP. Overall, we found MGMT
methylation in 74% (31/42) of the NENs investigated. A higher methylation degree was observed in welldifferentiated tumors and in tumors originating in the gastrointestinal tract. Comparing MSP and ABS results,
we demonstrate that the region analyzed by the MSP test is sufficiently informative of the MGMT methylation
status in NENs, suggesting that this predictive parameter could routinely be interrogated also in NENs. 相似文献
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Anna Maria Lavezzi Giulia Ottaviani Lorella Terni Luigi Matturri 《International journal of developmental neuroscience》2006,24(6):365-371
The aim of this study was to investigate the histological and biological features of the human cerebellar cortex development and differentiation. We analyzed 52 brains of fetal and infant death victims, aged from 17 gestational weeks to 12th postnatal month. In particular, in the cerebellar cortex at different ages we evaluated, besides the structural aspects, the expression of several biomarkers implicated in proliferative processes (c-fos, PCNA and apoptosis). We observed morphological patterns progressively evolving every month, from the indefinite structure of the second gestational trimester to the four-layered structure (external granular layer, molecular layer, Purkinje cell layer, internal granular layer) of the late fetal cortex and subsequently to the three-layered postnatal definitive morphology, due to involution of the external granular layer. The evaluation of the biological features of the cerebellar cortex showed high proliferative activity mainly confined to the transient external granular layer in prenatal life, and high apoptotic index after birth. Thus, the histological examination, better with the support of biomarker investigations, allows with accuracy to describe the dynamic sequence of steps that occur in human cerebellar cortex development and to establish in each case the age, namely the pre- or postnatal month of life. Consequently, we can diagnose delayed or altered processes of differentiation during the development of the human cerebellar cortex. 相似文献
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Larciprete G Valensise H Barbati G Di Pierro G Jarvis S Deaibess T Gioia S Giacomello F Cirese E Arduini D 《The journal of obstetrics and gynaecology research》2007,33(5):635-640
AIM: The aim of this study was to explore a birthweight prediction model using ultrasound determined tissue thickness (SCTT) parameters. METHODS: We measured routine ultrasonographic biometric parameters and in addition, fetal SCTT in 201 healthy singleton pregnancies. Mid-arm fat and lean mass, mid-thigh fat and lean mass, subscapular fat mass and abdominal fat mass (AFM) were measured in order to calculate a birthweight prediction model. Ultrasound measurements were analyzed using an 'anovarepeated measures model'. The growth rate (beta-slope) of the selected parameters was computed and the correlation coefficient with the birthweight and the Kendall rank correlation tau, were calculated. RESULTS: From the ultrasound determined SCTT parameters, only abdominal circumference (AC), AFM, and MTLM showed a statistically significant trend. The beta-slope of mid-thigh lean mass was excluded since it exhibited significant correlation with the beta-slope of AFM. The final regression model could be calculated as: birthweight (gr.) = intercept +alpha(1)(AFM beta-slope) + alpha(2)(AC beta-slope), where alpha(1), alpha(2) represent regression coefficients. CONCLUSIONS: We provide a graphical birthweight prediction model for clinical practice using conventional and specific ultrasound measurements of fetal subcutaneous tissue thickness. This model is based upon an overall analysis of the ultrasound estimated body components. 相似文献
9.
B Ricci 《Experimental eye research》1987,44(3):459-464
An experimental study was conducted on eight litters of newborn rats to evaluate the effects of supplemental oxygen administration on the retinal vasculature. The animals and their mothers were kept inside a pressure chamber and treated for the first 5 days of life. On the sixth day, they were removed and kept for five more days under room air and normobaric conditions. Three litters received continuous flow oxygen at 80% at a compression pressure of +81 kPa, one litter oxygen at 80% at a pressure of -39.5 kPa atms and three other litters received oxygen at 80% under normobaric conditions. The eighth litter was treated with room air oxygen at a compression pressure of +81 kPa. A severe retinopathy with marked retinal neovascularization was seen only in the newborn animals of the litters that received oxygen supplementation under normobaric or hypobaric conditions. Retinal vessels showed no pathological changes in the litters treated with hyperbaric normoxia or hyperoxia. It is possible to hypothesize that the prolonged period of oxygen supplementation failed to produce harmful effects on the retinal vasculature because the moderate hyperbarism caused mild retinal and choroidal vasoconstriction thus preventing excessive oxygen transport to the inner retina from the choroid during hyperoxia without inducing structural damage to the retinal tissue. 相似文献
10.
Francesco Leo Paolo Scanagatta Pierangelo Baglio Davide Radice Giulia Veronesi Piergiorgio Solli Francesco Petrella Lorenzo Spaggiari 《European journal of cardio-thoracic surgery》2007,31(5):780-782
OBJECTIVE: A higher mortality has been reported after pneumonectomy over the age of 70. The aim of the study was to quantify the additional risk due to age after standard pneumonectomy for lung cancer by a case-control study. METHODS: Our clinical database was reviewed to search for patients aged 70 years or more who underwent standard pneumonectomy for lung cancer between 1998 and 2005. A control group of patients younger than 70 (one case/two controls) was matched for sex, cardiovascular disease, American Association of Anaesthetists score, respiratory function, side of pneumonectomy, induction chemotherapy and stage. Overall mortality and morbidity were compared. Long-term survival data were also analysed. RESULTS: During the considered period, 35 patients aged 70 years or more underwent pneumonectomy (30 males, median age 73 years, 15 right-sided procedures). The control group was composed of 70 patients. The two groups were homogeneous in the variables used for matching. Overall mortality and morbidity were 11.4 and 54.2% in the elderly group as compared to 4.3 and 41.6% in controls (p-value not significant). Elderly patients experienced a higher rate of respiratory complications (25.7%) as compared to controls (8.3%, p=0.01). At univariate analysis, the only risk factor for death was the occurrence of respiratory complications (OR 6.5, CI 1.8-18.2). At multivariate analysis, age >or=70 years (OR 5.36, CI 1.48-19.3) and preoperative chemotherapy (OR 7.65, CI 2.04-28.6) were confirmed as predictors of respiratory complications. Five-year survival was 17.5% in the elderly group and 53.6% in the control group (p=0.003). Elderly patients with a better respiratory function (FEV1>70%) had a 5-year survival of 45.4%. CONCLUSIONS: In the elderly patients, the risk of respiratory complications after pneumonectomy is increased as compared to younger patients with equivalent respiratory function. Age and preoperative chemotherapy are independent risk factors for respiratory complications. A lower mortality and a better long-term survival are obtained in elderly patients with a better respiratory function (FEV1>or=70%). 相似文献